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101.
102.
We take up the existence and global behavior of positive continuous solutions of the following nonlinear parabolic equation in (n?2) with boundary conditions u=0 on and u(x,0)=u0(x). The nonlinear term is required to satisfy some conditions related to a functional class , which we introduce in this paper and will be called parabolic Kato class in the half space. Our approach is based on potential theory. 相似文献
103.
Magdalini Lada 《Journal of Algebra》2009,321(10):2798-2811
104.
The complex interplay between dislocations and deformation-induced twinning leads to a relatively poor formability of magnesium at room temperature. For understanding the complicated behavior of this metal, a novel model is presented. It is based on a variational principle. Within this principle based on energy minimization, dislocation slip is modeled by crystal plasticity theory, while the phase decomposition associated with twinning is considered by sequential laminates. The proposed model captures the transformation of the crystal lattice due to twinning in a continuous fashion by simultaneously taking dislocation slip within both, possibly co-existent, phases into account. (© 2011 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
105.
We study the existence of positive solutions of the m-polyharmonic nonlinear elliptic equation m(−Δ)u+f(⋅,u)=0 in the half-space , n?2 and m?1. Our purpose is to give two existence results for the above equation subject to some boundary conditions, where the nonlinear term f(x,t) satisfies some appropriate conditions related to a certain Kato class of functions . 相似文献
106.
107.
108.
Z. Malek V. Balek D. Garfinkel-Shweky S. Yariv 《Journal of Thermal Analysis and Calorimetry》1997,48(1):83-92
The dehydration and dehydroxylation of the smectites, beidellite and montmorillonite (dioctahedral) and saponite and laponite (trioctahedral), were investigated by ETA, DTA, TG and X-ray diffractions. There are differences between the behaviors of di- and trioctahedral clays which are due to the differences in the ability of the exchangeable cations to migrate into hexagonal holes of the SiO4 network and due to the fact that the dehydroxylation and recrystallization of dehydroxylated trioctahedral smectites occur simultaneously, whereas there is a temperature gap of about 300°C between the dehydroxylation and the recrystallization of dioctahedral smectites.Dedicated to Dr. Robert Mackenzie on the occasion of his 75th birthdayThe authors wish to thank Laporte Industries, Inc. UK for the laponite sample.This research was supported under Project No. C12-219, Grant No. HRN5544 G002069, U.S.-IsraelCooperative Development Research Program, Office of the Science Advisor, U.S. Agency for International Development. 相似文献
109.
Alkasrawi Malek Galbe Mats Zacchi Guido 《Applied biochemistry and biotechnology》2002,98(1-9):849-861
The effect of process stream recirculation on ethanol production from steam- pretreated softwood based on simultaneous saccharification
and fermentation (SSF) was investigated for two process configurations. In the first configuration, a part of the stillage
stream after distillation was recycled and, in the second configuration, the liquid after SSF was recycled. The aim was to
minimize the energy consumption in the distillation of the fermentation broth and in the evaporation of the stillage, as well
as the use of fresh water. However, recirculation leads to an increased concentration of nonvolatiles in the first configuration,
and of both volatiles and nonvolatiles in the second configuration. These substances might be inhibitory to the enzymes and
the yeast in SSF. When 60% of the fresh water was replaced by stillage, the ethanol yield and the productivity were the same
as for the configuration without recirculation. The ethanol production cost was reduced by 17%. In the second configuration,
up to 40% of the fresh water could be replaced without affecting the final ethanol yield, although the initial ethanol productivity
decreased. The ethanol production cost was reduced by 12%. At higher degrees of recirculation, fermentation was clearly inhibited,
resulting in a decrease in ethanol yield while hydrolysis seemed unaffected. 相似文献
110.
Malek Ennaifer Taroub Bouzaiene Chokri Messaoud Moktar Hamdi 《Natural product research》2020,34(18):2634-2638
AbstractIn Tunisia, Pelargonium graveolens is widely consumed as a food aromatizing hydrosol. Recent studies have shown the potential of plant solvent-free extracts as food and pharmaceutical natural additives. Accordingly, in this study, we investigate the phenolic content, the volatile fractions of green P. graveolens extracts such as infusion and decoction, and we evaluate their biological activities. The total phenolic content of the infusion (27.05?mg GAE/gDM) is significantly different from that of decoction (31.2?mg GAE/gDM). The GC-MS analysis identified about twenty volatile components in both extracts. The DPPH inhibition and the β-carotene bleaching tests of the infusion and the decoction had considerable results. Besides, infusion and decoction exhibited a relatively high anti-acetyl-cholinesterase activity and a considerable antimicrobial activity against S. aureus, among three tested pathogenic bacteria. 相似文献